Skip to content

All Products

Aviation Intelligence

Alerts & Airspace

Free Pilot Tools & Widgets

RC Aviation

Games & Learning

Weather Research & More

Pilot Resources

My Airports

Your shortcuts, saved on this device. Search to add an airport.

No airports saved yet. Add the fields you visit most.

Ask ATIS

Route on-time record

HOU to ONT: most on-time flights and the best time to fly

Houston (William P. Hobby Airport) to Ontario (Ontario International Airport). 362 nonstop flights in Jun 2025 to May 2026, 82% arrived within 15 minutes and 0.3% were cancelled. The most reliable flight number was Southwest 1577 at 8:05 AM.

Flying on a specific date? We’ll adjust for the month, the weekday and the forecast.

HOU → ONT

Houston to Ontario: 362 nonstop flights a year

On time (12 months)

82%

Cancelled

0.3%

avg delay 11 min

Best time to leave

Before 9 AM

89% on time vs 74% noon to 3 PM

Most reliable airline

Southwest

82% chance on time

Check HOU to ONT fares

Fares open on our travel partner (Aviasales). Pick the flight number you chose here.

Most reliable nonstop flights

Ranked by the chance the flight operates and arrives within 15 minutes of schedule, from Jun 2025 to May 2026 records.

  1. #1 · Southwest 1577

    8:05 AM → 9:30 AM3h 25m nonstop

    Local times, typical schedule. Last flown 2026-05-31.

    81%

    chance on time

    On time (history)
    79%
    Cancelled
    1.9%
    Avg arrival delay
    11 min
    • Arrived on time 79% of the time (53 flights, Jun 2025 to May 2026).
    • Leaves in this route's most on-time window (Before 9 AM: 89% on time; Noon to 3 PM: 74%).
    • Departs outside HOU's trouble window (noon to 6 PM, when 80% of its 40 ground stops and delay programs started).
    • Short track record (53 flights), so its score leans on the airline's record at this hour.

    Limited track record · 53 flights

    Find Southwest 1577 fares Opens this date on Aviasales

  2. #2 · Southwest 3865

    8:55 PM → 10:30 PM3h 35m nonstop

    Local times, typical schedule. Last flown 2026-04-06.

    78%

    chance on time

    On time (history)
    75%
    Cancelled
    0.0%
    Avg arrival delay
    17 min
    • Arrived on time 75% of the time (32 flights, Jun 2025 to May 2026).
    • Never cancelled in 32 scheduled flights.
    • Departs outside HOU's trouble window (noon to 6 PM, when 80% of its 40 ground stops and delay programs started).
    • 54% of its delay minutes came from the plane arriving late from an earlier flight.

    Limited track record · 32 flights

    Find Southwest 3865 fares Opens this date on Aviasales

Airlines on this route

Season-adjusted chance of operating and arriving on time.

  • Southwest Airlines82%

    362 flights · 82% on time as flown · 0.3% cancel

On time by departure time

All airlines, scheduled local departure, Jun 2025 to May 2026.

  • Before 9 AM89%

    116 flights · avg delay 7 min

  • Noon to 3 PM74%

    92 flights · avg delay 13 min

  • 3 to 6 PM83%

    53 flights · avg delay 15 min

  • 6 to 9 PM79%

    42 flights · avg delay 18 min

  • After 9 PM79%

    30 flights · avg delay 13 min

Best day: Tuesday (90%). Worst: Sunday (76%).

Smarter routing

Nearby airports that run more on time

  • IAH → SNA 87% chance on time

    George Bush Intercontinental Airport to John Wayne Orange County International Airport · 1,094 flights a year · 54 mi from your airports · yours: 82%

    Rank flightsFares

On time by month

All airlines, Jun 2023 to May 2026. Several years per month, so one stormy season doesn't define a month. Travel-month estimates use this seasonal pattern.

J
82
F
88
M
81
A
84
M
72
J
75
J
75
A
87
S
90
O
85
N
81
D
74

What delays this route

  • Late-arriving aircraft57%
  • Airline (crew, maintenance, boarding)33%
  • Air traffic control and airport volume8%
  • Severe weather1%

Share of delay minutes by the cause airlines report to the US DOT.

Historical odds, not a guarantee. Built from the US DOT Bureau of Transportation Statistics on-time reports (Jun 2025 to May 2026), FAA ground stop and delay program advisories, and 20 years of airport weather observations. Covers US airlines that report to the DOT; schedules are flights operated recently, so confirm times when you book. ATIS Alerts is not affiliated with any airline. Fares are what Aviasales travelers saw in recent searches (USD, one way, 1 adult), not live quotes; the partner site shows the current price. Fare links go to our travel partner and may earn us a commission at no cost to you. Affiliate disclosure

Finding the most reliable connections from HOU to ONT…

HOU to ONT questions

What time of day is best to fly HOU to ONT?
Before 9 AM: 89% of flights arrived on time, against 74% for departures noon to 3 PM. Later flights inherit delays from earlier ones, so the first departures of the day usually run best.
Which airline is most on time from HOU to ONT?
Southwest, with a season-adjusted 82% chance of operating and arriving on time over 362 flights. The adjustment compares each airline with what the route did in the months it flew, so a carrier that skipped a stormy month gets no free credit.
What is the worst month for delays on HOU to ONT?
May (72% on time); the best was September (90%), averaged over Jun 2023 to May 2026.
Is this a prediction for my flight?
No. These are historical odds from the US DOT on-time reports, FAA advisories and airport weather records. Check your flight status and the FAA delay board on the day you fly.

More routes from HOU

Live status: FAA delays and ground stops